Measurement of transdermal alcohol is potentially a very unobtrusive, inexpensive and accurate way of continuously studying the alcohol consumption behavior of subjects in research and field settings as well as for monitoring special populations. Several innovative technological advances in electrochemical sensing and engineering are proposed that will result in a novel transdermal alcohol sensing system to measure blood alcohol concentration. The proposed sensing system will go beyond the current Giner patented technology and constitute new, innovative, and potentially patentable technology. The new sensor system in the Giner WrisJAS" rWristworn Transdermal Alcohol Sensor) family will require low maintenance, be more comfortable to wear, allow transfer of data from the home, be more resistant to tampering and be less expensive to manufacture. It detects blood alcohol transdermally (10- >400 mg/dl). The commercial goal is to sell the complete alcohol monitoring system for under $1100. The proposed Phase II program will continue and extend the successful research and development in the Phase I program. The Phase II objectives are to: 1) Complete Additional Refinements to Enhance Performance and Economy of Sensor Features 2) Develop Second Generation of Wireless Data Transmittal and Automated Data Analysis. 3) Design WrisTAS" 7 Enclosures (sensor module, electronics module and wristband/cable) 4) Evaluate the New WrisTAS" Products in Clinical Settings. Commercial Potential: There are a number of markets for a continuous, nohinvasive alcohol monitor including: 1) Research and clinical treatment programs. 2) Emergency room setting for individualsthat are unconscious, incapacitated, or unable to exhale forcibly. 3) Monitoring of professionals with or without known alcohol problems in positions involving public safety (aviation, nuclear, medical). 4) Monitoring drivers with prior DWI/DUI convictions. 5) Criminal justice system, where the court needs to monitor alcohol abstinence of convicted criminals on parole, probation or house arrest.